mtlog-analyzer for Visual Studio Code

Real-time validation for mtlog message templates in Go code.

Features

• 🔍 Real-time diagnostics - See template errors as you type
• 🎯 Precise error locations - Jump directly to problematic code
• 📊 Severity levels - Errors, warnings, and suggestions
• ⚡ Quick fixes - Automatic fixes for common issues
• ⚙️ Configurable - Customize analyzer path and flags

What it catches

// ❌ Error: Template has 2 properties but 1 argument
logger.Information("User {UserId} logged in from {IP}", userId)
//                                                      ^^^^^^ Quick fix: Add 1 missing argument

// ⚠️ Warning: Using @ prefix with basic type
logger.Debug("Count is {@Count}", 42)

// 💡 Suggestion: Property name should be PascalCase
logger.Information("User {userId} completed action", "user123")
//                        ^^^^^^ Quick fix: Change to 'UserId'

Quick Fixes

The extension provides automatic fixes for common issues:

• PascalCase property names - Converts userId to UserId, user_id to UserId, etc.
• Argument mismatches - Adds placeholder arguments for missing properties or removes excess arguments
• Format specifier corrections - Fixes invalid format specifiers (e.g., {Count:d3} → {Count:000})
• Context key constants - Extracts repeated string literals to constants
• LogValue() method generation - Creates stub implementations for safe logging of complex types

Apply fixes by clicking the light bulb (💡) or pressing Ctrl+. (Windows/Linux) or Cmd+. (macOS) when your cursor is on the diagnostic.

Requirements

• Go 1.21 or later
• mtlog-analyzer (automatically detected or can be installed via prompt)

Installation

1. Install this extension from the VS Code Marketplace

2. The extension will automatically find mtlog-analyzer if it's installed. If not found, you'll be prompted to install it with one click.

Automatic Detection

The extension searches for mtlog-analyzer in the following locations (in order):

1. Configured path in settings
2. System PATH
3. Go binary locations:
   • $GOBIN
   • $GOPATH/bin
   • ~/go/bin (default Go install location)
   • Platform-specific locations (e.g., /usr/local/go/bin on macOS)

Configuration

Example configuration:

{
  "mtlog.analyzerPath": "C:\\Go\\bin\\mtlog-analyzer.exe",
  "mtlog.analyzerFlags": ["-strict"]
}

How it works

The extension runs mtlog-analyzer when you save Go files, parsing the output and displaying diagnostics directly in the editor. It's designed to work alongside gopls without interference.

Troubleshooting

"mtlog-analyzer not found"

If the extension can't find mtlog-analyzer:

1. Automatic Installation: Click "Install" when prompted by the extension
2. Manual Installation: Run go install github.com/willibrandon/mtlog/cmd/mtlog-analyzer@latest
3. PATH Issues:
   • On macOS: If VS Code is launched from Dock/Spotlight, it may not inherit your shell PATH
   • Solution: Launch VS Code from terminal with code . or restart VS Code after installation
4. Custom Location: Specify the full path in settings:

   {
     "mtlog.analyzerPath": "/full/path/to/mtlog-analyzer"
   }
   

No diagnostics appearing

• Check Output panel (View → Output → mtlog-analyzer) for errors
• Verify the analyzer works: mtlog-analyzer your-file.go
• Ensure you're saving the file (analysis runs on save)

License

MIT